This was on my caller ID this morning.  No message.

caller ID: Keller William.  Rec'd call Nov 3, 2015 at 9:58am PST.  I picked up and heard recording "goodbye" and the caller hung up.

maybe its a scam. careful guys

It's a Scam "Mike" & you know it! You see "Mike", you've just given it away. You've identified who the caller is claiming to be & we know better than that. It's Shills like you who expose Scams even better than we do. You're so quick to try to validate your Scams that your brains can't keep up with your greed. There are other ways that we can tell that you're a Shill & that this is a Scam. We'll just let you think about that for a while though "Mike".
Nice work there "Mike". You've failed.
Skeff Ett Liv!
Gunnar